Spaces:
Running on Zero
Running on Zero
File size: 2,056 Bytes
2cf2375 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 | #pragma once
#include <cstdint>
#include <vector>
#include <algorithm>
#include <iostream>
namespace Bestemshe {
struct State {
uint8_t M; // Total stones captured (K_self + K_opp)
uint8_t K_self; // Active player's Kazan
uint8_t K_opp; // Opponent's Kazan
uint8_t board[10]; // Pits 0-4 (Self), 5-9 (Opponent)
};
// Sows from pit `i` (0..4) and returns if a capture occurred.
// If valid, writes results to `next_s`.
inline bool ExecuteMoveAndFlip(const State& s, int i, State& flipped_out, bool& empties_opponent) {
if (s.board[i] == 0) return false;
State next_s = s;
int pieces = next_s.board[i];
next_s.board[i] = 0;
int current_pit = i;
if (pieces == 1) {
current_pit++;
if (current_pit==10) current_pit = 0;
next_s.board[current_pit]++;
} else {
next_s.board[i] = 1;
pieces--;
while (pieces > 0) {
current_pit++;
if (current_pit==10) current_pit = 0;
next_s.board[current_pit]++;
pieces--;
}
}
bool is_capture = false;
// Even Parity Capture on opponent's side (pits 5..9)
if (current_pit >= 5 && current_pit <= 9) {
if ((next_s.board[current_pit] & 1) == 0) {
uint8_t captured = next_s.board[current_pit];
next_s.K_self += captured;
next_s.M += captured;
next_s.board[current_pit] = 0;
is_capture = true;
}
}
// Evaluate if opponent is completely emptied
empties_opponent = true;
for (int p = 5; p <= 9; ++p) {
if (next_s.board[p] > 0) {
empties_opponent = false;
break;
}
}
// Flip board for opponent's turn perspective
flipped_out.M = next_s.M;
flipped_out.K_self = next_s.K_opp;
flipped_out.K_opp = next_s.K_self;
for (int p = 0; p < 5; ++p) {
flipped_out.board[p] = next_s.board[p + 5];
flipped_out.board[p + 5] = next_s.board[p];
}
return is_capture;
}
} // namespace Bestemshe |